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Abstract By changing the precursor lead‐to‐sulfur molar ratio in the synthesis of colloidal PbS nanosheets, the lateral size of the nanosheet can be tuned in a wide range from 100 nm to 1500 nm while keeping its thickness around 2.4 nm. Using chloroalkane molecules with a long carbon‐chain as the capping ligands can further reduce the lateral size down to 20 nm. The concentration of the chloroalkane in the reaction solution and the reaction temperature also have significant effects on the lateral size. At room temperature, nanosheets with a small lateral size exhibit a narrow light‐emission linewidth. The same nanosheets also show a sharp exciton peak near the band edge in the optical absorption spectrum.
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Boost the Lead Conversion Efficiency for the Synthesis of Colloidal 2D PbS Nanosheets
In the synthesis of colloidal PbS nanosheets, the supernatant of the reaction solution is reused to boost the lead conversion efficiency. It doubles the conversion efficiency of the lead precursors to the PbS nanosheets. The nanosheets synthesized by reusing the supernatant have similar morphology, nearly identical thickness, and optical properties as the original ones, confirmed by transmission electron microscopy, X‐ray diffraction, and photoluminescence spectroscopy. This method reduces the toxic Pb‐containing waste during the synthesis, a step toward the green and scalable synthesis of colloidal 2D PbS nanosheets.
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- Award ID(s):
- 1905217
- PAR ID:
- 10443405
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- physica status solidi (a)
- Volume:
- 220
- Issue:
- 3
- ISSN:
- 1862-6300
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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